At http://phys.org/print298105107.html … a possibly revealing post on the processes occurring at the junction of tectonic plates – in particular subduction zones where one plate is sliding under another. This is thought to be responsible for volcanism and deep earthquakes. It is also clearly a hypothesis as in the next paragraph it reads, many aspects of subduction are still poorly understood and research is critical to understanding where such orces could lead to human disasters (a reference I suppose to the Boxing Day Indian Ocean earthquake and tsunami). In other words, the consensus model is a paper model only. Has the process of subduction actually been observed?
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